Kit Harington Thinks Son Will Get 'Shock of His Life' When Baby No. 2 Comes Home: 'Really Exciting'

Angela Weiss / AFP

Kit Harington is excited about his growing family.

Harington, 36, chatted with Entertainment Tonight ahead of the premiere of his Apple TV+ series, Extrapolations, where he said his 2-year-old son is "about to get the shock of his life," when he and wife Rose Leslie bring home their second baby, due later this year.

"I don't know if he's really conceptually understood anything yet," Harington said of his son knowing what's ahead.

"He's just loving life. My boy loves life," the proud dad beamed. "He charges around, and I think he's going to be a great older brother. It's just really exciting."

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Samir Hussein/WireImage Kit Harington (left) stands beside his wife Rose Leslie (right)

RELATED: Kit Harington Reveals Wife Rose Leslie Is Pregnant, Expecting Their Second Baby

Ahead of their second child, the couple is taking a "practical approach" to the preparations.

"We're really practical about it at the moment. And actually, almost too practical," Harington joked, saying that they were "romantic" about getting ready to welcome their first.

"And this other one, we're like, 'Right, okay, let's get.' We know how efficient we have to be. Let's get down to parenting."

Dimitrios Kambouris/Getty Images Rose Leslie and Kit Harington

The Game of Thrones alum continued, "My mum says that she never remembers us being little kids or the early parenting much because you're so present in it. And I think that's what kids allow you to be, is incredibly present in the moment, 'cause you've got no choice."

When it comes to his new show's discussion of climate change, Harington said it's one that's a "regular conversation" between him and Leslie.

"I look at it in some ways of like, our parent's generation were oblivious. We're becoming very aware," Harington explained. "And it would be our duty and my children's duty to deal with it. It'll be the great challenge of their generation, but it doesn't stop at being the challenge of ours as well."